A communication system is a facility which facilitates the communication between two or more entities such as communication devices, network entities and other nodes. A communication system may be provided by one or more interconnected networks. A communication device can be understood as a device provided with appropriate communication and control capabilities for enabling use thereof for communication with others parties. The communication may comprise, for example, communication of voice, electronic mail (email), text messages, data, multimedia and so on. A communication device typically enables a user of the device to receive and transmit communication via a communication system and can thus be used for accessing various service applications.
In cellular systems a network entity in the form of a base station provides a node for communication with mobile devices in one or more cells. A base station is often referred to as a ‘Node B’. There are many different techniques for processing signals for transmission between the base station and the user equipment. Typically the operation of a base station apparatus and other apparatus of an access system required for the communication is controlled by a particular control entity. The control entity is typically interconnected with other control entities of the particular communication network.
Cellular communication systems typically employ a network of base stations (Node Bs) to communicate with User Equipment under the co-ordination of a network controller. The node Bs comprises one or more receiver/transmitter antenna means to perform said communication which may be downlink (i.e. from the base Station to the User equipment or uplink (from the User Equipment to the NodeB. Adjacent Node Bs also communicates with each other.
As far as the base stations are concerned these may comprise an array of multiple antennae which are arranged radially to cover transmission and reception in a plurality of sectors.
Multiple Input/Multiple Output (MIMO) systems are known systems which use multiple antennas at the transmitter and receiver (of e.g. base stations) along with advanced digital signal processing to improve link quality and capacity. More data can be received/sent where there are more antennae elements.
With MIMO systems however they usually need two to four times the number of transceivers compared to the Single Input/Single Output (SISO) systems. Generally also in MIMO systems the transceiver function is split into more sectors and so the number of components such as High Gain Power Amplifiers (HPAs) can be substantial in comparison. In particular HPAs contribute a large portion of the cost of such systems as well as the power consumption and thus eventually carbon emissions also.
It is an object of the invention to provide for a MIMO system which provides for an efficient system which however reduces the number of components required as well as reducing power consumption.